The issue gained attention on social media after an islander shared a photo of a bacon sandwich with visible mould on the bread.
The snack was purchased from the General Hospital canteen on Friday 29 November.
Pictured: The individual who posted the image alleged that after raising the issue with staff, they were advised to share their concerns online.
Health apologised “unreservedly” for the error in a statement provided to Express following the incident.
The department said that new control checks have been introduced as a result.
The full statement said: “The HCS Catering Service apologises unreservedly for an incident at one of its public catering outlets on Friday 29 November.
“The bread used by HCS is supplied locally and delivered seven days a week with a minimum of three days’ use-by-date.
“The Hazard Analysis Critical Control Point Team has reviewed the incident and has introduced new control checks.
“We will continue working with our team and suppliers to prevent a similar incident from happening again.”